Apparatus, system, and method for calibration of a media processing device

ABSTRACT

A method, apparatus, and system for calibration of a media processing device are provided. The method may include providing a calibration sub-routine where the calibration sub-routine includes a plurality of calibration operations to be performed in sequence. The method may further include associating an audible note with each calibration operation and generating the audible note for each calibration operation as each respective calibration operation is performed, where the audible note is generated by a frequency of operation of a motor. The audible note associated with one calibration operation may be different from the audible note associated with another calibration operation.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. Non-Provisionalapplication Ser. No. 13/274,080, filed on Oct. 14, 2011, the disclosureof which is hereby incorporated by reference.

TECHNOLOGICAL FIELD

Embodiments of the present invention generally relate to solutions forproviding a mechanism by which a media processing device is calibratedto properly function with various types of media. More specifically, thepresent invention provides an apparatus, system, and method forcalibrating a media processing device based upon the media received bythe device in order to improve and enhance the media processingoperations.

BACKGROUND

Media processing devices, such as printers, may be configured to processmultiple kinds of media including substrates such as labels, receipts,cardstock, and cards among many other media types. As different forms ofmedia have different characteristics, each type of media may require themedia processing device to implement different calibration settings inorder to process the media properly. For example, a label printer may beconfigured to print on labels of multiple sizes such that the printermay require media size related calibration settings to be appropriatelyset to accurately and repeatably print on labels of a given size beingused in the printer. Similarly, the color of the media substrate mayvary between media types and in order to accurately reproduce images,the media processing device may require appropriate color calibrationsettings in order to compensate for media color variations. Variouscalibration settings within the media processing device may affect thequality and reliability of the processing operation such that the propercalibration settings may minimize or eliminate errors while enhancingthe processing quality. In the case of a media printer, the calibrationsettings may improve print quality and/or color reproduction, accuratelylocate the printed image on a media substrate, reduce media waste, etc.

BRIEF DESCRIPTION OF DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention and,together with a general description of the invention given above, andthe detailed description of the embodiments given below, serve toexplain the principles of the invention.

FIG. 1 illustrates a block diagram of an example apparatus forimplementing example embodiments of the present invention;

FIG. 2 illustrates an example embodiment of a media processing deviceaccording to embodiments of the present invention;

FIG. 3 depicts an example embodiment of marked media as may be processedby example embodiments of the present invention;

FIG. 4 is a flowchart illustrating operations performed by an exampleembodiment of a method according to the present invention; and

FIG. 5 is a schematic representation of a media processing deviceconfigured to generate an audible note according to an exampleembodiment of the present invention.

SUMMARY OF THE INVENTION

The present invention is directed to an apparatus, system, and methodfor calibration of a media processing device. Example embodiments of thepresent invention may include a method of calibrating a media processingdevice including providing a calibration sub-routine where thecalibration sub-routine includes a plurality of calibration operationsto be performed in sequence. The method may further include associatingan audible note with each calibration operation and generating theaudible note for each calibration operation as each respectivecalibration operation is entered, where the audible note is generated bya frequency of operation of a motor, such as a feed motor. The audiblenote associated with each calibration operation may be different fromthe audible note associated with each other calibration operation. Theaudible note associated with each calibration operation may be a musicalnote. The audible notes associated with the plurality of calibrationoperations may collectively form an expected sequence of audible noteswhen the calibration operations are performed in sequence. The expectedsequence of audible notes may be complete in response to the pluralityof calibration operations being performed in sequence successfully. Theexpected sequence of audible notes may be incomplete in response to atleast one of the calibration operations not being performedsuccessfully.

Example embodiments of the present invention may include an apparatuswhere the apparatus includes a controller and a motor, such as a feedmotor. The controller may be configured to perform a calibrationsub-routine comprising a plurality of calibration operations. The motormay be configured to emit an audible note in response to operating ateach of a plurality of frequencies, where the audible note is differentfor each of the plurality of frequencies. Each of the plurality ofcalibration operations may be configured to be performed with the motoroperating at a particular frequency to generate a particular audiblenote associated with the calibration operation. The audible noteassociated with each calibration operation may be different from theaudible note associated with each other calibration operation. Theaudible note associated with each calibration operation may be a musicalnote. The audible notes associated with the plurality of calibrationoperations may collectively form an expected sequence of audible noteswhen the calibration operations are performed in sequence. The expectedsequence of audible notes may be completed in response to the pluralityof calibration operations being performed in sequence successfully. Theexpected sequence of audible notes may be incomplete in response to atleast one of the plurality of calibration operations not being performedsuccessfully.

Example embodiments of the present invention may include a method forcalibrating a media processing device including advancing media past asensor in a first direction, determining a white-level for the media,determining a black-level for the media based on a first mark on themedia; and reversing the media past the sensor in a second direction,opposite the first direction, to determine a mark length based on thefirst mark on the media. The method may further include advancing themedia past the sensor in the first direction in response to determiningthe mark length. The method may also include determining a page lengthin response to advancing the media past the sensor in the firstdirection in response to determining the mark length. The white-levelmay be verified in response to determining the black level.

Another example embodiment of the present invention may include anapparatus including at least one processor and at least one memoryincluding computer program code, the at least one memory and thecomputer program code configured to, with the processor, cause theapparatus to at least advance media past a sensor in a first direction,determine a white-level for the media, determine a black-level for themedia based on a first mark on the media, and reverse the media past thesensor in a second direction, opposite the first direction, to determinea mark length based on the first mark on the media. The apparatus mayfurther be caused to advance the media past the sensor in the firstdirection in response to determining the mark length. The apparatus maystill further be caused to determine a page length in response toadvancing the media past the sensor in the first direction in responseto determining the mark length. The apparatus may further be caused toverify the white-level in response to determining the black level.

DETAILED DESCRIPTION

Some embodiments of the present invention will now be described morefully hereinafter with reference to the accompanying drawings, in whichsome, but not all embodiments of the invention are shown. Indeed,various embodiments of the invention may be embodied in many differentforms and should not be construed as limited to the embodiments setforth herein; rather, these embodiments are provided so that thisdisclosure will satisfy applicable legal requirements. Like referencenumerals refer to like elements throughout.

As used herein, the terms “data,” “content,” “information” and similarterms may be used interchangeably to refer to data capable of beingtransmitted, received, displayed and/or stored in accordance withvarious example embodiments. Thus, use of any such terms should not betaken to limit the spirit and scope of the disclosure. Further, where acomputing device is described herein to receive data from anothercomputing device, it will be appreciated that the data may be receiveddirectly from the another computing device or may be received indirectlyvia one or more intermediary computing devices, such as, for example,one or more servers, relays, routers, network access points, basestations, and/or the like.

The present invention provides an apparatus, system, and method forperforming a media calibration procedure in a media processing device.Media processing devices, such as printers, may be configured to printon a variety of media substrates such as tags, labels, receipts, cards,etc. with various size, shape, color, and surface characteristics. Themedia substrates may be paper, synthetic media, woven or non-wovenmaterials, and may or may not include radio frequency identification(RFID) transponders. Each of these media characteristics may require theadjustment of various media processing device settings in order tooptimize media processing quality and minimize waste. While embodimentsof the present invention may be used with a number of media processingdevices, such as thermal printers, ink jet printers, intermediatetransfer media printers, laminators, or the like, example embodimentswill be described with respect to thermal printing devices. However, aswill be apparent to one of ordinary skill in the art, the apparatus,systems, and methods disclosed herein may be used with any number ofmedia processing devices. The calibration process may be initiated,monitored, or otherwise controlled by a user where the user may includea person initiating the calibration, troubleshooting the mediaprocessing device, performing initial set-up of the device at a factory,an installer, a service technician, or any person involved in theoperation of the media processing device.

FIG. 1 illustrates a schematic block diagram of controller 102 inaccordance with some example embodiments. In this regard, FIG. 1illustrates an apparatus that may comprise or be employed on a mediaprocessing device, such as that illustrated in FIG. 2, and which may beconfigured to control or perform calibration of a media processingdevice in accordance with one or more embodiments. However, it should benoted that the components, devices or elements illustrated in anddescribed with respect to FIG. 1 below may not be mandatory and thussome may be omitted in certain embodiments. Additionally, someembodiments may include further or different components, devices orelements beyond those illustrated in and described with respect to FIG.1.

Referring now to FIG. 1, the controller 102 may include or otherwise bein communication with processing circuitry 210 that is configurable toperform actions in accordance with example embodiments disclosed herein.The processing circuitry 210 may be configured to perform dataprocessing, application execution and/or other processing and managementservices according to one or more example embodiments. In someembodiments, the controller 102 or the processing circuitry 210 may beembodied as or comprise a chip or chip set. In other words, thecontroller 102 or the processing circuitry 210 may comprise one or morephysical packages (e.g., chips) including materials, components and/orwires on a structural assembly (e.g., a baseboard). The structuralassembly may provide physical strength, conservation of size, and/orlimitation of electrical interaction for component circuitry includedthereon. The controller 102 or portion thereof, such as the processingcircuitry 210, may therefore, in some cases, be configured to implementan embodiment of the invention on a single chip or as a single “systemon a chip.” As such, in some cases, a chip or chipset may constitutemeans for performing one or more operations for providing thefunctionalities described herein.

In some example embodiments, the processing circuitry 210 may include aprocessor 212. In some embodiments, such as that illustrated in FIG. 1,the processing circuitry 210 may further include memory 214. However, itwill be appreciated that in some example embodiments, the processingcircuitry 210 may not include memory 214. The processing circuitry 210may be in communication with or otherwise control a communicationinterface 218. As such, the processing circuitry 210 may be embodied asa circuit chip (e.g., an integrated circuit chip) configured (e.g., withhardware, software or a combination of hardware and software) to performoperations described herein. However, in some embodiments, theprocessing circuitry 210 may be embodied as a portion of a computingdevice, such as may be implemented on or in operative communication witha media processing device.

The communication interface 218 may include one or more interfacemechanisms for enabling communication with other devices and/ornetworks. In some cases, the communication interface 218 may be anymeans such as a device or circuitry embodied in either hardware, or acombination of hardware and software that is configured to receiveand/or transmit data from/to a network and/or any other device or modulein communication with the processing circuitry 210. By way of example,the communication interface 218 may enable sending and/or receiving datato and/or from another device, such as a local or a remote server. Inthis regard, the communication interface 218 may include, for example,an antenna (or multiple antennas) and supporting hardware and/orsoftware for enabling communications with a wireless communicationnetwork and/or a communication modem or other hardware/software forsupporting communication via cable, digital subscriber line (DSL),universal serial bus (USB), Ethernet or other methods.

In some example embodiments, the memory 214 may include one or morenon-transitory memory devices such as, for example, volatile and/ornon-volatile memory that may be either fixed or removable. The memory214 may be configured to store information, data, applications,instructions or the like for enabling the controller 102 to carry outvarious functions in accordance with one or more example embodiments.For example, the memory 214 may be configured to buffer input data forprocessing by the processor 212. Additionally or alternatively, thememory 214 may be configured to store instructions for execution by theprocessor 212. As yet another alternative, the memory 214 may includeone or more databases that may store a variety of files, contents ordata sets. Among the contents of the memory 214, applications may bestored for execution by the processor 212 in order to carry out thefunctionality associated with each respective application. In somecases, the memory 214 may be in communication with the processor 212,such as via a bus, for passing information among components of thecontroller 102.

The processor 212 may be embodied in a number of different ways. Forexample, the processor 212 may be embodied as various processing meanssuch as one or more of a microprocessor or other processing element, acoprocessor, a controller or various other computing or processingdevices including integrated circuits such as, for example, an ASIC(application specific integrated circuit), an FPGA (field programmablegate array), or the like. In some example embodiments, the processor 212may be configured to execute instructions stored in the memory 214 orotherwise accessible to the processor 212. As such, whether configuredby hardware or by a combination of hardware and software, the processor212 may represent an entity (e.g., physically embodied in circuitry—inthe form of processing circuitry 210) capable of performing operationsaccording to embodiments of the present invention while configuredaccordingly. Thus, for example, when the processor 212 is embodied as anASIC, FPGA or the like, the processor 212 may be specifically configuredhardware for conducting the operations described herein. Alternatively,as another example, when the processor 212 is embodied as an executor ofsoftware instructions, the instructions may specifically configure theprocessor 212 to perform one or more operations described herein.

In some example embodiments, the processor 212 (or the processingcircuitry 210) may be embodied as, include, or otherwise control acalibration controller 220. As such, the calibration controller 220 maybe embodied as various means, such as circuitry, hardware, a computerprogram product comprising computer readable program instructions storedon a computer readable medium (for example, the memory 214) and executedby a processing device (for example, the processor 212), or somecombination thereof. The calibration controller 220 may be capable ofcommunication with one or more of the memory 214 or communicationinterface 218 to access, receive, and/or send data as may be needed toperform one or more of the functionalities of the calibration controller220 as described herein.

Width Detection

Embodiments of the present invention may be configured to perform acalibration sub-routine to accurately calibrate the calibration settingsof a media processing device for the media to be received therein. Onecalibration setting may include the media width for which the mediaprocessing apparatus is configured to calibrate the media width based onthe detected width of the media or the detected width of an adjustablemedia guide configured to guide the media into the media processingdevice.

In an example embodiment of width detection, the media processing devicemay include one or more sensors, in communication with controller 102,that may be used to detect the width of media as it is fed or insertedinto the media processing device. The sensors may include infrared (IR)reflective sensors that may be sampled, for example, as 8-bit A/D countvalues by the width detection calibration sub-routine. The sensors maydetect the location of a media guide or the physical presence of themedia. In such an embodiment, the media processing apparatus may be ableto detect a narrow or wide media substrate as it is fed or inserted intothe media processing device. In an example embodiment in which there aretwo standard media widths (e.g., a narrow width and a wide width), twosensors may be used in concert to calibrate the media width calibrationsetting and to determine if an error exists with the media presence ormedia width.

One method with which the two sensors may work in concert to calibratethe media width is through detecting or sensing whether or not media ispresent at one or both of the sensors as illustrated in the table below.FIG. 2 illustrates a media processing apparatus 300 including a mediaprocessing path 310, proximate which are media sensor one 320 and mediasensor two 330. Optionally, the media processing device 300 may includea removable/replaceable media guide 340. Media sensor one 320 and mediasensor two 330 may be configured to detect the presence of media and/orthe presence of a media guide 340. The media guide 340 may be availablein multiple widths, each width corresponding to a respective mediawidth. Table 1 below illustrates example sensor readings from mediasensor one 320 and media sensor two 330 and media detection conclusionsthat may be drawn from the example sensor circuitry. The media sensor320 and media sensor 330 may be proximity sensors, infrared reflectivesensors, or suitable sensor that may detect the presence of media or amedia guide.

TABLE 1 Sensor one State Sensor two State (Wide) (Narrow) ConclusionMedia Present Media Not Present Error - Sensor 2 defective Media PresentMedia Present Wide Media detected Media Not Present Media Not Present NoMedia detected Media Not Present Media Present Narrow Media detected

The detection of media only at sensor two corresponds to a narrow mediabeing detected while detection at both sensor one and sensor twocorresponds to a wider media substrate being detected and overlayingboth media sensors. As a wide media guide 340 may be configured tooverlay the narrow media sensor (sensor two 330), the presence of mediais detected in the same manner as the detection of a media guide atsensor two. With present/not-present functionality, the controller isnot capable of differentiating between media presence and media guidepresence at sensor two. While Table 1 illustrates a use of sensor one320 and sensor two 330 in a present/not-present fashion, further detailregarding the media width calibration setting may be determined usingthe sensor transition for each of sensors one and two (e.g., when thesensor changes from no-detection to a detection state) when media isinitially loaded or when the media is exhausted and no longer detected.Table 2 illustrates additional functionality when using the transitiondetection at sensor one 320 and sensor two 330. In the exampleembodiment using detection of a transition at sensor one and sensor two,the controller may be able to differentiate between media presence andmedia guide presence, thereby using existing hardware to enhance themedia processing device functionality.

TABLE 2 Sensor one Sensor two Sensor one Sensor two State StateTransition Transition Conclusion Not Not Present Present No Guide,present present Wide Media Not Not Not Present No Guide or presentpresent present Guide, Narrow Media Not Present Present Present WideGuide, present Wide Media Load

In order to determine when the media is out, the calibration sub-routinemay use a single sensor to detect when the media is no longer present.The single sensor used may be determined based upon the signals seen atsensor one and sensor two as outlined above. For example, when narrowmedia is detected, the calibration sub-routine may rely upon sensor two330 to determine if the media is out. When wide media is used, eithersensor one 320 or sensor two 330 may be used to determine if the mediais out. When wide media is used with a wide media guide, sensor one 320may be used to determine if media is out.

However, the condition may arise in which the media is out and thecontroller 102 does not detect the media out condition. For example, ifthe media processing device is configured with a narrow media guide 340(where media sensor two detects the guide present), such a configurationmay use sensor two for the media out sensor. Should a wide media guidebe later installed, the sensor two may be obscured by the wide mediaguide and sensor two may not accurately detect a media out condition.Because there is no detectable difference between the media guide andthe media, the controller may believe that media is present. As media isfound to be present, the media width calibration sub-routine may not beinitiated and the media out functionality may be lost. For this reason,a user may manually initiate the media width calibration through a keysequence.

Media Sensing Calibration

Example embodiments of the present invention may include an apparatus,system, and method by which information about the media used, or to beused, is measured and stored (e.g., in memory 214) through a mediacalibration sub-routine performed, for example, by calibrationcontroller 220. The proper measurement and gathering of this mediainformation may be critical for the controller to properly discern howto work with the media that is selected. The media calibrationsub-routine may begin when the media processing device detects a “mediaout” condition (as outlined above) where there is no longer any mediabeing inserted or fed along a feed path or processing path of the mediaprocessing device 300. The detection of the media out condition can bedetermined by the media processing device actively sensing that themedia is out (e.g., through the use of media sensors 320 and 330disposed on or proximate the feed path) or via manual input from a user,such as through a key sequence. The media sensors 320 and 330 maymeasure the presence of media through raw A/D counts, such that a validrange may be from 20 counts to 255 counts.

The media calibration sub-routine may be initiated when the print headis in a closed state. When the print head is in a closed state, and themedia out condition has been detected, the media calibration sub-routinemay be initiated upon detection of media (e.g., through the use of themedia sensors used to determine the media out condition, as describedabove). The controller may monitor the media sensors through atransition from a low value (e.g., an A/D count value of 50 or less) toa higher value. The value detected through the media sensors prior tothe transition from the low value to the high value may be established(e.g., calibrated) as the end-of-media threshold calibration setting,thereby assuming that the low value means that no media is present. Avariance may be included in the end-of-media threshold to minimizeerroneous “media out” warnings. The end-of-media threshold may be thevalue sensed by the media sensor prior to the transition to a highvalue, where the threshold includes a variance of −30 counts to +10counts, for example.

Optionally, the end-of-media threshold may be a user adjustable settingwithin the memory 214 of the controller 102. If an invalid value isspecified by the user (e.g., a value below 20 counts or above 255counts), the previously loaded value (stored in memory 214) may be used.If the value stored in the memory 214 is invalid, a default value may beused, such as 200 counts. The default value may also be userconfigurable. The value stored by the media calibration sub-routine forthe end-of-media threshold calibration setting may be represented as:

eopThresh=t0pl−10

Where eopThresh is the end-of-media threshold value in A/D counts andt0pl is the actual measured value for the “end of media.” This mayposition the high threshold for the end-of-media system 10 A/D countscloser to the media than is actually detected (e.g., the end of mediaequation incorporates an offset).

Upon detection of the media and calibration of the end-of-mediathreshold calibration setting, a time delay may be implemented. The timedelay, for example, 1.5 seconds, may be implemented to give a user timeto advance or insert the media forward to a platen roller or feed rollerwithin the media processing device to properly position the media foroperation of the media processing device.

While the above media calibration sub-routine has been described withrespect to calibration in response to detection of media with the mediasensors, it may be desirable for the media calibration sub-routine to beinitiated without the presence of media. In such an embodiment, a secondcalibration process may be performed, possibly at the point ofmanufacture of the media processing device. The media processing devicemay be configured with a media guide (e.g., media guide 340 of FIG. 2).The controller 102 of the media processing device 300 may use sensors320 and/or 330 to detect the width of an installed media guide. Thesensors may, for example, be infrared (IR) reflective sensors that aresampled as 8-bit A/D counts by the controller to determine the mediaguide width calibration setting. This process of calibration of themedia guide width may be performed without media such that an accuratemeasure of the media guide is achieved. The media calibrationsub-routine for the media guide width calibration may also serve tocalibrate a cutter (e.g., the width of cut required to cut the media)and detect the installed media guide. An advantage to a mediacalibration sub-routine that does not require media to be present to beinitiated may include remote execution of a command version ofcalibration. In some cases it might be desirable to initiate calibrationfrom a remote location which may be achieved with a calibrationsub-routine that does not require media to be present as disclosedherein.

Media Type Calibration

Example embodiments of the present invention may include an apparatus,system, and method by which information about the media used, or to beused, is measured and stored in a media calibration sub-routine, whichmay be performed by calibration controller 220. The proper measurementand gathering of this information may be critical for the controller toproperly discern how to process the media that is selected. Two examplemedia types that may be used in a media processing device according tothe present invention may include continuous media (e.g., media that isa continuous, unmarked web substrate) and mark media (e.g., media thatis prepared as a single substrate and marked between forms or sectionsof the substrate). In such an example, a user may enter the type ofmedia they are using into the controller 102, using a user interfacethat may be implemented on the media processing device or a user inputthat is configured to communicate with the controller via thecommunications interface 218, such that a media calibration sub-routineconfigured for that specific media may be appropriately executed.

FIG. 3 illustrates an example embodiment of a media processing device300 receiving a web of marked media 360. The marked media 360 includesmarks 362 and 364. The marks may be disposed on the printed,non-printed, or both sides of the media web 360. The marks 362, 364, mayprovide reference points from which processing, cutting, and presentingof the media is measured. The illustrated embodiment of a marked mediaweb 360 is shown partially obscuring the narrow media sensor 330 whilenot obscuring the wide media sensor 320. As such and as outlined above,the media processing device 300, through the media width calibrationsub-routine, may recognize the media as narrow media.

Example embodiments of a media calibration sub-routine may include thecalibration of several settings. For example, the media calibrationsub-routine may include a white-level calibration, an out-of-paper levelcalibration, and a top of form (TOF) marker sensitivity calibration.When continuous media is selected, the media calibration sub-routine maybe limited to calibration of the white-level which is recognized as thevalue that the controller 102 has determined is a reliable indication ofthe whiteness of the media sampled over a number of steps, where a“step” is an incremental movement of a feed roller or platen rollerwithin the media processing device.

In order for a white-level calibration value to be considered stable,the value should not vary more than 20 A/D counts over the samplingperiod and the value should not fall below the end-of-media thresholdoutlined above. In an example embodiment, the white-level of the mediamay be sampled over 75 steps of media using a white-level sensordisposed along the media feed path configured to read the reflectivity,emissivity, or white-level of the surface of the media substrate. Insuch an embodiment, the feed motor may feed the media a predeterminedprint speed such that sampling occurs after each step. Should the valuevary more than 20 A/D counts over a predetermined distance, such as 15mm of media, the sampling process may restart as the consistency of thewhite-level value may be deemed suspect.

Upon achieving a stable calibrated value for the white-level, twoadditional parameter settings may be configured. The first calibrationsetting may be the end-of-media threshold as outlined above. If aninvalid value for the end-of-media threshold is stored in the memory,such as memory 214 of the controller 102, a default value of 255 may beused. This parameter may be used as part of a system to detect thedifference between a black-mark on the media and a media-out condition.

The second parameter setting may be the “Top-of-Form marker sensitivity”or TOF marker sensitivity calibration setting which may be a useradjustable setting within the system. The TOF marker sensitivity settingis used to determine if a black mark is detected on the media. The TOFmarker sensitivity calibration setting may be measured in A/D countswith a valid range of 0 counts to 255 counts. If an invalid value isstored in the memory, such as memory 214 of the controller 102, adefault value of 120 may be used. When the system internally queries todetermine if the white-level sensor is over a black mark, the returnedA/D count value of the selected sensor is compared to the TOF markersensitivity. If the A/D count value is above the TOF marker sensitivity,a black mark is assumed present at the white-level sensor. If the A/Dcount value is below the TOF marker sensitivity, no black mark isdetected at the sensor. In continuous media calibration, the TOF markersensitivity may be set with the following formula:

${sens} = {{w\; {Max}} + \frac{{tOpl} - {w\; {Max}}}{2}}$

Where sens is the TOF marker sensitivity, wMax is the highest valuedetected at the white-level sensor during the white-level verificationprocedure and tOpl is the A/D count level detected as the media outlevel during the initial media present calibration operation. Thisformula effectively sets the level at which a black mark is detected. Ina typical white media calibration case, with a wMax value of 222 and atOpl value of 26, the TOF Marker Sensitivity is 124. An AD level abovethis level would be detected as a TOF mark.

While black mark sensing is not necessary when using continuous media,such a calibration process and calibration parameter settings may beused if marked media is used without recalibrating the system or if theuser-setting to determine continuous media or mark media is improperlyselected.

In an example embodiment wherein mark media is selected, top-of-form(TOF) synchronization calibration sub-routine may be enabled. The TOFsynchronization may include white-level detection as outlined above;however, as a continuous substrate of a consistent white-level is notanticipated, the distance over which the white-level is calibrated maybe increased to a distance such as 37.5 mm rather than a shorterdistance, such as 15 mm, for continuous media. The selection of theincreased distance may be predicated on the absolute maximum TOF blackmark length, which may be approximately 32 mm.

The media calibration sub-routine for marked media may differ from themedia calibration sub-routine for continuous media if the calculatedwhite-level is greater than the detected out-of-paper level, meaningthat end-of-media threshold is “brighter” than with paper present. Insuch an example, the end-of-media threshold level may be re-calculatedwith the following formula:

${opl} = {{w\; {Min}} + \frac{{w\; {Min}} - {tOpl}}{2}}$

Where wMin is the lowest value detected during the white-levelverification procedure and tOpl is the A/D count level detected duringthe media out level during the width analysis calibration operation.

Upon completion of the white-level calibration, the media calibrationsub-routine may initiate a mark calibration sequence. The markcalibration sequence may begin with feeding the media along the mediaprocessing path (e.g., path 310 of FIG. 2) until a transition from thewhite-level to a black mark is detected at the white-level sensor. Insuch an embodiment, the controller 102 may be configured to anticipatethe detection of a transition to a darker mark detected at thewhite-level sensor. If the white-level sensor encounters a transition toa brighter mark, the white-level verification sequence may be requestedagain as the calibrated white-level value may be suspect. The detectionby the controller 102 of an increased white-level when anticipating ablack mark may cause the controller 102 to generate an error messageindicative of the issue and present this error message to a user or toanother device, such as a printer server, network device, accessory,indicator light, internal data bus, as a hardware handshake, etc. Thiserror may be considered informational as the media calibrationsub-routine may continue without user intervention until a maximumcalibration time and/or length is achieved without successful completingthe media calibration sub-routine.

Upon the white-level sensor encountering a transition from thewhite-level to a darker area, indicative of a black mark or TOF mark,the mark calibration sequence, as implemented by the controller 102, maybegin sampling the black mark with the white-level sensor to determine ablack-level. From the samples taken across the black mark, the lowestA/D count value, or darkest level, is preserved. The sampling maycontinue until the sensor detects a value that is within the originalbounds found during the white-level analysis indicating that the sensoris beyond the black mark.

The mark sensitivity may then be set using the following equation:

${sens} = {( {{w\; {Min}} + \frac{{w\; {Max}} - {w\; {Min}}}{2}} ) + {( {{{bm}\; {Min}} - \frac{( {{w\; {Min}} + \frac{{w\; {Max}} - {w\; {Min}}}{2}} )}{5}} )*2}}$

Where sens is the mark sensitivity, wMax is the highest value detectedduring the white-level verification procedure, wMin is the lowest valuedetected during the white-level verification procedure, and bmMin is theminimum value detected over the black mark. The parentheticalcalculations involving wMin and wMax are simply a formula to find thecenter of the detected white-level, and the division by five andmultiplication by two position the sensitivity between the bmMin and theverified white-level.

The media calibration sub-routine may then continue to feed media usingthe established sensitivity value to determine the next black mark. Oncethe next black mark is found, the size of the black mark may be sampledby counting each step that is at least as dark as the sensitivity valueestablished above.

Once the A/D count value read by the white-level sensor is less than theabove value (e.g., the end of the mark is reached), the black marklength is set. Another parameter, serving as a “garbage filter,” mayalso be set at this time. The garbage filter may be user adjustable andmay be measured as a distance, such as in millimeters. The function ofthe garbage filter setting is to determine what amount of mark-levelactivity on the sensor is too small to be considered a valid mark. If amark that is in the detection process is detected to be shorter than thegarbage filter, the mark is ignored. Conversely, a maximum black marklength is also established such that a mark that is larger than themaximum black mark length is interpreted as an out-of-media condition.The garbage filter may be set using the following formula:

${garb} = {( \frac{markLen}{5} )*2}$

Where garb is the garbage filter value and markLen is the detectedlength of the black mark. This formula positions the garbage length justbelow half the length of a valid mark.

The media calibration sub-routine may then calibrate the page lengthcalibration setting. In such an embodiment, the media may be fed forwarduntil a valid mark is detected. At this time the media out detection maybe running as well as the black mark detection such that the mediaprocessing device may be capable of determining if the media runs out.If the next mark is detected before the page length is the distance fromthe media sensor (e.g., media sensor one 320 or two 330) to the cut line(e.g., the line at which the media is cut within the media processingdevice), the page is considered invalid and a new page lengthcalculation may be started. This allows media with dual-section marks,such as boarding passes, to be used provided the first mark distance isless than the media sensor to cut line distance. In response to the nextmark being found, the page length setting may be calibrated.

Reduced Media Consumption During Calibration

Example embodiments of the present invention may consume less media tocomplete the calibration sub-routine procedure than standard calibrationprocedures. A flowchart illustrating operations performed by, or inrelation to a method of an example embodiment is presented in theflowchart of FIG. 4. It will be understood that each block of theflowchart, and combinations of blocks in the flowchart, may beimplemented by various means, such as hardware, a computer programproduct comprising a computer readable medium storing programinstructions (e.g., software, firmware, and the like), processor,circuitry and/or other device. For example, one or more of theprocedures described above may be embodied by computer programinstructions. In this regard, the computer program instructions whichembody the procedures described above may be stored by a memory deviceof an apparatus employing an embodiment of the present invention andexecuted by a processor in the apparatus. As will be appreciated, anysuch computer program instructions may be loaded onto a computer orother programmable apparatus (e.g., hardware) to produce a machine, suchthat the resulting computer or other programmable apparatus embody meansfor implementing the functions specified in the flowchart block(s).These computer program instructions may also be stored in acomputer-readable memory that may direct a computer or otherprogrammable apparatus to function in a particular manner, such that theinstructions stored in the computer-readable memory produce an articleof manufacture the execution of which implements the function specifiedin the flowchart block(s). The computer program instructions may also beloaded onto a computer or other programmable apparatus to cause a seriesof operations to be performed on the computer or other programmableapparatus to produce a computer-implemented process such that theinstructions which execute on the computer or other programmableapparatus provide operations for implementing the functions specified inthe flowchart block(s).

Accordingly, blocks of the flowchart support combinations of means forperforming the specified functions, and combinations of operations forperforming the specified functions. It will also be understood that oneor more blocks of the flowchart, and combinations of blocks in theflowcharts, can be implemented by special purpose hardware-basedcomputer systems which perform the specified functions, or combinationsof special purpose hardware and computer instructions.

In an example embodiment, an apparatus for performing the methods ofFIG. 4 may comprise processing circuitry (e.g., processing circuitry210) configured to perform some or each of the operations (400-450)described below. The processing circuitry may, for example, beconfigured to perform the operations (400-450) by performing hardwareimplemented logical functions, executing stored instructions, orexecuting algorithms for performing each of the operations. Additionallyor alternatively, the apparatus may comprise means for performing one ormore of the operations described above. In this regard, according to anexample embodiment, examples of means for performing operations 400-450may comprise, for example, the processing circuitry 210, the processor212, memory 214 and/or a device or circuit for executing instructions orexecuting an algorithm for processing information as described furtherbelow.

The calibration sub-routine involving marked media may initially advancemedia past the platen roller or feed roller to ensure the media is fullyengaged by the platen roller or feed roller. In some exampleembodiments, the calibration sub-routine may then substantially followthe steps outlined above and further described herein with respect tothe flowchart of FIG. 4 with the media feed direction for each flowchartoperation illustrated by the illustrated arrows. The calibrationsub-routine may sample white-level of the media to establish a baselinewhite-level and ensure a variation of less than a predefined thresholdto ascertain the white-level of the media at 400. The media may then beadvanced until a black mark is detected at the white-level sensor at410. The calibration sub-routine may then determine the black-level ofthe black mark at 420 and verify the white-level after the black mark isfound at 430. Once the white-level baseline is found, the black mark isfound, the black-mark level is found, and the post-black markwhite-level is verified, the motor may operate in reverse such that thepreviously measured black mark (initially measured for black level), ismeasured again for the size of the black mark at 440. This re-use of thesame black mark for multiple steps of the calibration sub-routinereduces the amount of media consumed by not advancing the media to thesubsequent black mark. Once the black mark length is established, themedia may then be advanced to the cutter and/or the presenter at 450 tobe cut and/or ejected, leaving the next media substrate ready forprocessing.

Audible Confirmation of Calibration

During the media calibration sub-routine which includes a plurality ofcalibration operations, the process may fail or stop at any calibrationoperation due to a variety of problems. As it may be difficult for auser to diagnose the point-of-failure of the calibration sub-routine, amechanism by which the user is alerted to the specific operation of thecalibration sub-routine may be desirable.

Provided herein is an example embodiment of a method for alerting a useras to the progress of the calibration sub-routine. Each calibrationoperation within the calibration sub-routine may be assigned an audiblenote where the audible note may be generated by operating a motor of themedia processing device, such as the media processing device's feedmotor, at different frequencies during the calibration sub-routine. Inan example embodiment in which the motor is a stepper motor, a signal todrive the motor is embodied as a wave with a frequency of phase changes(from low to high) such that each phase change is a step of the motor.The frequency with which these phase changes occur affect the speed ofthe driven motor and also may produce an audible tone at the drivenfrequency. As varying the frequency of operation of the feed motor mayaffect the speed at which the calibration sub-routine is performed, insome example embodiments, the calibration sub-routine logic may beindependent of time or duration. Optionally, if the calibrationsub-routine logic employs a time component, the time component may beadjusted to accommodate the variation in feed motor speed introduced byoperation of the feed motor at various frequencies.

The audible notes may be generated by driving the phase changes to thefeed motor at a rate or frequency equivalent to the desired pitch. Astepper motor, for example, may be driven with a signal that includes aphase change from a high state to a low state, each transition to a highstate representing a step of the motor. Thus, the frequency of the phasechange corresponds to a speed of operation of the stepper motor. Thefrequency of the phase change of the motor may produce vibrations of thedesired frequency which may propagate through parts of the feed motor orcomponents attached thereto making the notes audible. For example, thephase change frequency of the motor may produce vibrations in the motorcase and spindle, which in turn may propagate through a gear trainthereby making the note audible. Optionally, a note-generating componentmay be attached to the motor or proximate thereto which may resonate atthe operating frequencies of the feed motor to produce the audiblenotes. Such a note-generating component may be a diaphragm or othercomponent capable of converting the phase change frequencies of themotor into an audible note. FIG. 5 illustrates a schematic diagram ofexample embodiment of the generation of an audible note within a mediaprocessing device. The motor 520 is driven by the controller 510 at aspecific phase change frequency corresponding to a desired audible note.While the motor 520 may or may not include sufficient structure togenerate an audible note, additional components of the media processingdevice may further propagate and enhance the volume of the note tocreate a more audible note. For example, the driven motor 520 maypropagate the phase frequency through a gear or gear train 530 which mayenhance the audible note. Additionally or alternatively, the drivenmotor 520 may cause a portion of the housing 540 to resonate at thedriven frequency to create the audible note. Additionally oralternatively, the driven motor 520 may further cause a diaphragm 550 orother structure to resonate at the driven frequency, thereby producingthe audible note. While components such as the housing 540, the geartrain 530, or the diaphragm 550 may enhance or increase the volume of anoperating frequency of the motor 520, such components generally do notsubstantially change the audible tone generated.

An example of the audible notes as applied to phases of the calibrationprocess are summarized below in Table 3, which illustrates examplecalibration operations of the calibration sub-routine of marked media,in accordance with some example embodiments.

TABLE 3 Operation Name Description Musical Note Advance Media Advancethe paper 10 mm past G (392 hz) the platen to ensure it is fully underplaten control White Balance Sample white area of media B (493 hz) for15 mm, must not swing more than 20 AD steps, if it does, restart phaseSearch Find any black more than D (587 hz) Blackness .5 v higher thanthe white balance, find the peak. Verify White Search for the medialevels C♯ (554 hz) Balance found by white balance again Search NextReverse Motor Direction, D (587 hz) BM scan for the mark again MeasureBM Motor still reversed, measure D (587 hz) Size the size of the markFind Page Forward Motor direction, find High G (783 hz) Size the nextmark to measure distance between marks Reset Paper Advance distancebetween head Normal Motor and cutter to synchronize, Operation based cutand eject. on speed settings

As shown above, operations of an example calibration process andcalibration sub-routine are identified by the “operation name”, a briefdescription of the calibration operation is provided under“description,” and an example frequency of the audible note generated isidentified. The frequencies selected may be user selected or may befixed. The frequencies are preferably within a commonly audible rangeand may be sequenced to form a recognizable, expected sequence ofaudible notes such as a tune for which any note omissions are readilyapparent to a user. For example, the audible notes may form anevenly-stepped sequence with a frequency increase to the next highernote at each phase. Any note omissions would be apparent to a user aswould any stoppage prior to completing the musical sequence.

Table 4 below illustrates named musical notes that correspond toparticular frequencies; however, an infinite number of notes existacross the range of audible frequencies, most without a musical notename. The table below is merely representative of commonly recognizedmusical notes that may be used in example embodiments of the presentinvention.

TABLE 4 Notes Frequency (octaves) A 55.00 110.00 220.00 440.00 880.00 A♯58.27 116.54 233.08 466.16 932.32 B 61.74 123.48 246.96 493.92 987.84 C65.41 130.82 261.64 523.28 1046.56 C♯ 69.30 138.60 277.20 554.40 1108.80D 73.42 146.84 293.68 587.36 1174.72 D♯ 77.78 155.56 311.12 622.241244.48 E 82.41 164.82 329.64 659.28 1318.56 F 87.31 174.62 349.24698.48 1396.96 F♯ 92.50 185.00 370.00 740.00 1480.00 G 98.00 196.00392.00 784.00 1568.00 A♭ 103.83 207.66 415.32 830.64 1661.28

Table 5 illustrates example calibration operation of the calibrationsub-routine of plain or continuous media.

TABLE 5 Phase Name Description Musical Note Advance Media Advance thepaper 10 mm past G (392 hz) the platen to ensure it is fully underplaten control White Balance Sample white area of media B (493 hz) for15 mm, must not swing more than 20 AD steps, if it does, restart phaseReset Paper Feed 92 mm Pitch sweep from 493 hz to 783 hz (B to G)As illustrated in Table 5, the “reset paper” operation of thecalibration sub-routine includes a pitch sweep which may further enablea user to better determine the current calibration operation. Should themedia processing device stop in the process of the pitch sweep, thedegree to which the reset paper calibration operation was complete maybe evident by the last pitch heard (e.g., the lower the pitch, the lessprogress through the reset paper calibration operation).

Varying the frequency with which a motor is driven may createundesirable effects, particularly when the frequency generated is aresonant frequency which causes components of the media processingdevice to resonate or vibrate at a frequency that may be detrimental toprinting, such as a frequency which resonates to the point of causingchatter (e.g. undesirable vibration of the printhead, platen, or mediawhich may degrade print quality). Applicant has identified a number ofacceptable motor operating speeds which correspond to phase changefrequencies which may be employed without detrimental effects togenerate audible tones that may communicate the calibration operation byvirtue of association of each calibration operation with a frequency.Such audible tones generated by components of a media processing deviceoperating within acceptable ranges of speeds and frequencies may producethe additional benefit of alerting a user as to the current calibrationoperation of a media processing device and alert a user of a faultycalibration operation in the event the calibration sub-routine does notproperly complete.

While the present invention has been illustrated by the description ofthe embodiments thereof, and while the embodiments have been describedin considerable detail, it is not the intention of the applicant torestrict or in any way limit the scope of the appended claims to suchdetail. Additional advantages and modifications will readily appear tothose skilled in the art. Therefore, the invention in its broaderaspects is not limited to the specific details, representativeapparatus, methods, and illustrative examples shown and described.Accordingly, departures may be made from such details without departurefrom the spirit or scope of applicant's general inventive concept.Further, it is to be appreciated that improvements and/or modificationsmay be made thereto without departing from the scope or spirit of thepresent invention as defined by the following claims.

That which is claimed:
 1. A method for calibrating a media processingdevice comprising: advancing media past a sensor in a first direction;determining a white-level for the media; determining a black-level forthe media based on a first mark on the media; and reversing the mediapast the sensor in a second direction, opposite the first direction, todetermine a mark length based on the first mark on the media.
 2. Themethod of claim 1, further comprising: advancing the media past thesensor in the first direction in response to determining the marklength.
 3. The method of claim 2, further comprising determining a pagelength in response to advancing the media past the sensor in the firstdirection in response to determining the mark length.
 4. The methodaccording to claim 1, further comprising verifying the white-level inresponse to determining the black level.
 5. The method according toclaim 1, wherein determining a white-level for the media is performed asthe media is advanced past the sensor in the first direction.
 6. Themethod according to claim 5, wherein determining a black-level for themedia based on a first mark on the media is performed as the media isadvanced past the sensor in the first direction.
 7. The method accordingto claim 1, wherein determining a black-level for the media based on afirst mark on the media is performed in response to the sensorencountering a black mark on the media as the media is advanced in thefirst direction.
 8. The method according to claim 7, wherein the mediadirection is reversed in response to the sensor detecting the end of theblack mark as the media is advanced in the first direction.
 9. Themethod according to claim 2, wherein the media direction is reversedfrom the second direction to the first direction in response to reachingan end of the mark.
 10. An apparatus comprising at least one processorand at least one memory including computer program code, the at leastone memory and the computer program code configured to, with theprocessor, cause the apparatus to at least: advance media past a sensorin a first direction; determine a white-level for the media; determine ablack-level for the media based on a first mark on the media; andreverse the media past the sensor in a second direction, opposite thefirst direction, to determine a mark length based on the first mark onthe media.
 11. The apparatus of claim 10, wherein the apparatus isfurther caused to advance the media past the sensor in the firstdirection in response to determining the mark length.
 12. The apparatusof claim 11, wherein the apparatus is further caused to determine a pagelength in response to advancing the media past the sensor in the firstdirection in response to determining the mark length.
 13. The apparatusaccording to claim 10, wherein the apparatus is further caused to verifythe white-level in response to determining the black level.
 14. Theapparatus of claim 10, wherein causing the apparatus to determine awhite-level for the media is performed as the media is advanced past thesensor in the first direction.
 15. The apparatus according to claim 14,wherein causing the apparatus to determine a black-level for the mediabased on a first mark on the media is performed as the media is advancedpast the sensor in the first direction.
 16. The apparatus according toclaim 10, wherein causing the apparatus to determine a black-level forthe media based on a first mark on the media is performed in response tothe sensor encountering a black mark on the media as the media isadvanced in the first direction.
 17. The apparatus according to claim16, wherein the apparatus is further caused to reverse the mediadirection in response to the sensor detecting the end of the black markas the media is advanced in the first direction.
 18. The apparatusaccording to claim 11, wherein the apparatus is caused to reverse themedia direction from the second direction to the first direction inresponse to reaching an end of the mark.